This project is devoted to the development of spectroscopic methods of analysis for trace elements in biological samples. Current work is concerned with an investigation of plasma sources for emission spectroscopy and their use for simultaneous multielement analysis. Specific efforts have been directed to an atmospheric pressure DC plasma source and a low pressure microwave induced plasma. BIBLIOGRAPHIC REFERENCES: E.R. Johnson, C.K. Mann and T.J. Vickers, "Computer Controlled System for Study of Pulsed Hollow Cathode Lamps", Appl. Spectrosc., 30, 415 (1976). Christopher D. Keirs and Thomas J. Vickers, "DC Plasma Arcs for Elemental Analysis", Appl. Spectrosc., 31, (1977), in press.